To which knowledge area does the Collect Requirements process belong?

Quality Management processes focus on quality planning, assurance, and control - not on gathering stakeholder requirements.

Collect Requirements is the second process in the Project Scope Management knowledge area, sitting within the Planning process group. It involves determining, documenting, and managing stakeholder needs and requirements to meet project objectives, and its outputs - including the requirements documentation and requirements traceability matrix - directly feed into the Define Scope process.

Cost Management processes address estimating, budgeting, and controlling costs, which occur after requirements are already defined.

Integration Management processes coordinate and unify all other processes; they do not include requirements collection.